Mixed-reality systems, including virtual-reality (VR) and augmented-reality (AR) systems, have received significant attention because of their ability to create truly unique experiences for their users. For reference, conventional VR systems create a completely immersive experience by restricting their users' views to only virtual environments. This is often achieved through the use of a head-mounted device (HMD) that completely blocks any view of the real world. As a result, a user is entirely immersed within the virtual environment. In contrast, conventional AR systems create an augmented-reality experience by visually presenting virtual images (i.e. “holograms”) that are placed in or that interact with the real world.
As used herein, VR and AR systems are described and referenced interchangeably. Unless stated otherwise, the descriptions herein apply equally to all types of mixed-reality systems, which (as detailed above) include AR systems, VR systems, and/or any other similar system capable of displaying virtual images. As used herein, the term “virtual image” collectively refers to images rendered within a VR environment as well as images/holograms rendered in an AR environment.
Some of the disclosed mixed-reality systems use one or more on-body devices, such as HMD 100 shown in FIG. 1. HMD 100 provides a display that enables a user to view overlapping and/or integrated visual information (e.g., virtual images) in whatever environment the user is in, be it a VR environment, an AR environment, or any other type of environment. For instance, virtual content can be displayed on lens 105 and lens 110 of the HMD 100 for the user to view. Continued advances in hardware capabilities and rendering technologies have greatly improved how mixed-reality systems render virtual images.
Many mixed-reality systems also operate using eye tracking and iris recognition/detection modules. These modules are used to track or detect the user's eye in order to provide a more enjoyable experience for the user. For instance, with eye tracking, the mixed-reality system will be able to track the user's eye position to provide input into the system. With iris detection, the mixed-reality system can provide robust security features by ensuring that the proper user is using the mixed-reality system or that the mixed-reality system is being used in a proper manner (e.g., parental controls for young children). Many mixed-reality systems include a nosepiece 115 so the HMD 100 can be comfortably placed on the user's head. Located near this nosepiece 115 is a first camera 120 for tracking eye movements and eye characteristics of one eye and a second camera 125 for tracking eye movements and eye characteristics of the other eye. In this regard, first camera 120 and second camera 125 are placed near the user's eyes and are positioned directly towards those eyes to monitor movement and perform other types of detection. Sometimes, these tracking/detection devices utilize their own light sources to measure light reflecting from the user's eyes. Unfortunately, users often express feelings of discomfort as a result of these somewhat bulky cameras being positioned so near their eyes. As such, there is a need in the field to improve how eye tracking and iris recognition is performed in order to reduce or eliminate the discomfort felt by users of the mixed-reality system.
Additionally, as mixed-reality systems become more advanced, it is becoming more and more desirable to employ lasers and associated components (e.g., collimating optics, beam combiners, photodetectors/photodiodes, etc.) that have small/smaller form factors. Use of smaller units means that more hardware can be packaged together within the mixed-reality system at reduced costs. Therefore, in addition to improving eye tracking and iris detection, there is a substantial need in the field to reduce the size of laser-based systems.
The subject matter claimed herein is not limited to embodiments that solve any disadvantages or that operate only in environments such as those described above. Rather, this background is only provided to illustrate one exemplary technology area where some embodiments described herein may be practiced.